/Engine/Plugins/Experimental/LearningAgents/Source/LearningAgents/Public/LearningAgentsManager.h
Returns true if the given id is an agent used by the manager; Otherwise, false.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintPure, Category="LearningAgents", Meta=(AgentId="-1")) bool HasAgent ( const int32 AgentId ) const